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<h1 align="center">VLFEAT</h1>
<a href="#NAME">NAME</a><br />
<a href="#DESCRIPTION">DESCRIPTION</a><br />
<a href="#FILE%20SPECIFIERS%20(FILESPEC)">FILE SPECIFIERS
(FILESPEC)</a><br />
<a href="#SEE%20ALSO">SEE ALSO</a><br />
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<h2>NAME <a name="NAME" id="NAME"></a></h2>
<p style="margin-left:11%; margin-top: 1em">VLFeat &minus;
VisionLab Features Library</p>
<h2>DESCRIPTION <a name="DESCRIPTION" id="DESCRIPTION"></a></h2>
<p style="margin-left:11%; margin-top: 1em"><b>VLFeat</b> is a
collection of computer vision algorithms with a special focus on
image features such as SIFT and MSER.</p>
<p style="margin-left:11%; margin-top: 1em">The functionalities
offered by the library can be accessed either through its API, or
by means of command line and MATLAB programs. See the <b>SEE
ALSO</b> section for a list of the related command line programs
and for a pointer to the general documentation of the library.</p>
<h2>FILE SPECIFIERS (FILESPEC) <a name=
"FILE SPECIFIERS (FILESPEC)"></a></h2>
<p style="margin-left:11%; margin-top: 1em">Some commands in
<b>VLFeat</b> make use of &lsquo;file specifiers&rsquo; to
associate to one or more input files the appropriate
output/auxiliary files. A file specifier is a string such as
&lsquo;ascii://%.txt&rsquo; and contains two pieces of
information:</p>
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<p>The <b>file format</b> (in this case <i>ascii</i>). The
supported formats depend on the particular application. Two common
formats are <i>ascii</i> and <i>bin</i>(ary).</p>
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<p>&bull;</p>
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<p>A <b>name transformation rule</b> (in this case <i>%.txt</i>).
This is used to transform the name an input file into the name of
the corresponding output/auxiliary file. The transformed name is
comput by extracting the basename of the input file substituting it
to all occurences of the wildcard characer &lsquo;%&rsquo; in the
transformation rule (&lsquo;%%&rsquo;) passes the wildcard
character untouched.</p>
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<p style="margin-left:11%; margin-top: 1em">Recall that the
basename of a file name is obtained by stripping the directory
prefix (everything from the beginning up to the last
&lsquo;/&rsquo; or &lsquo;\&rsquo; character) and extension
(everything from the last &lsquo;.&rsquo; characeter (excluding the
prefix) to the end).</p>
<p style="margin-left:11%; margin-top: 1em">For instance, the
filespec &lsquo;ascii://%.txt&rsquo; and the input file
&lsquo;test.data&rsquo; specify a file named &lsquo;test.txt&rsquo;
in ascii (text) format.</p>
<p style="margin-left:11%; margin-top: 1em"><b>Partial file
specifiers</b><br />
Normally, a program provides default values for its file
specifiers. In this case, partial file specifier (with only the
file format or the name transformation rule are acceptable).</p>
<p style="margin-left:11%; margin-top: 1em"><b>File specifiers
equivalent to a file name</b><br />
A partial specifier such as &lsquo;file.txt&rsquo; is in effect
equivalent to the file name &lsquo;file.txt&rsquo;. If the
specifier is used in conjunction with multiple input files, this
causes the same file to be accessed multile times.</p>
<h2>SEE ALSO <a name="SEE ALSO"></a></h2>
<p style="margin-left:11%; margin-top: 1em"><b>sift</b>(1),
<b>mser</b>(1)</p>
<p style="margin-left:11%; margin-top: 1em">A. Vedaldi and B.
Fulkerson. VLFeat Library. <i>http://www.vlfeat.org/</i></p>
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